What is anaphylaxis?
Anaphylaxis is a serious and potentially life threatening allergic reaction that should always be treated as a medical emergency. It is important that symptoms are recognised early, and treated quickly with a medicine called adrenaline. An ambulance should always be called for a person having anaphylaxis and the operator informed that it is anaphylaxis. They should always be taken to hospital following treatment for suspected anaphylaxis.
What causes anaphylaxis?
Certain substances called ‘allergens’ can trigger this severe rapid onset allergic reaction. These include:
- Foods, such as cow’s milk, eggs, peanuts, tree nuts, fish, and shellfish are the most common food triggers, but many other foods have the potential to cause anaphylaxis.
- Medications (e.g. antibiotics, aspirin, anaesthetic drugs and chlorhexidine)
- Insect venom (e.g. bee and wasp stings)
- Latex (e.g. latex gloves, party balloons and condoms)
- Sometimes there is no known cause for an anaphylactic reaction. This is called idiopathic anaphylaxis.
Why does anaphylaxis occur?
An allergic reaction (including anaphylaxis) occurs because the body’s immune system reacts inappropriately in response to the presence of a food or substance that it wrongly perceives to be a threat. When this happens, chemicals such as histamine are released from cells in the blood and tissues. These can cause swelling in the skin, lips, mouth, throat or lower airway causing difficulty in swallowing and/or breathing.
What are the symptoms of an allergic reaction?
Mild to moderate allergic reaction:
- Swollen lips, face or eyes (angio-oedema)
- Itchy/tingling in the mouth
- Urticaria (“hives” or “nettle rash”)
- Abdominal pain
- Vomiting
- Sudden change in behaviour
ANAPHYLAXIS – Any of the above features PLUS any of the following:
- Airway: hoarse voice, difficulty swallowing, swollen tongue
- Breathing: persistent cough, wheeze, shortness of breath or difficulty breathing
- Circulation/consciousness: floppy, pale, collapse, suddenly sleepy, persistent dizziness
For more information on Anaphylaxis please take a look at the Factsheet links below:
Patient Stories
First-hand accounts from patients living with anaphylaxis.